guide
How far is the Moon from Earth? Choose a date and explore
The Moon is about 384,400 km (238,855 miles) from Earth on average, but the distance changes through its orbit. Choose a date below for centre-to-centre separation and one-way light time at 00:00 UTC. In our daily-sampled archive the separation ranges from 356,452 km to 406,687 km; those sampled extremes are specific to 2020-01-01 00:00 TDB through 2040-01-01 00:00 TDB, not universal limits.
Use the existing scientific archive
How far is the Moon on your chosen date?
Choose a date for the Earth–Moon distance and one-way light time at 00:00 UTC. This is an archive calculation, not a live spacecraft measurement.
Measured facts
- Distance at the recorded snapshot epoch
- 387,439 km · 0.003 AUThe epoch used by the embedded Solar System state.
- One-way light time
- 1.3 seconds
- Closest measured separation
- 356,452 km on 2034-11-26
- Farthest measured separation
- 406,687 km on 2025-11-20
- Mean separation
- 385,011 km7,306 daily samples.
- Variation across the archive
- 50,235 km
Kilometres, miles and the meaning of the average
NASA quotes a commonly used average of 384,400 kilometres, or 238,855 miles. That reference average is not the distance on every date. A mean computed from a particular archive and sampling schedule can differ slightly; COSMOS labels its sampled mean in Measured facts.
These are distances between the centres of Earth and the Moon. They are not an astronaut’s height above the lunar surface, a ground-station-to-reflector laser range or the length of a spacecraft route. The date calculator reuses the explorer’s Earth-centred JPL vectors rather than assuming a circular orbit.
Perigee, apogee and what "distance" means
The closest point of a lunar orbit is perigee and the farthest is apogee. The Sun and other perturbations change the orbit, so successive closest and farthest distances are not identical. The dated archive extremes answer a different question from a conventional average.
Astronomers also use the average Earth–Moon distance as a unit, the lunar distance, which is convenient for quoting distances of near-Earth objects.
How these numbers were produced
Cubic-Hermite interpolation of the shipped Earth-centred JPL Horizons state archive, sampled once per day across the declared coverage. Distances are magnitudes of the geometric position vectors; no light-time correction or planetary-orbit averaging is applied.
The provider tabulates the Moon every half day. The calculator interpolates its Earth-centred vector at the selected UTC midnight; the summary ranges and mean use one sample per day across the declared coverage. No values are extrapolated beyond the archive.
Light travel time is not spacecraft travel time
A radio signal takes about 1.3 seconds to cross the average Earth–Moon separation one way. The calculator divides its geometric separation by the speed of light; a round-trip signal has roughly twice that delay before adding processing time.
A spacecraft follows a trajectory with its own launch conditions, speed and mission goals. Dividing the distance by the speed of light does not predict a spacecraft arrival time. Likewise, this geocentric calculation does not predict whether you can see the Moon from your location tonight.
Seeing the variation in the explorer
COSMOS renders the Earth–Moon pair at true relative size and separation at the selected date. Move the date control and the separation changes in place; the scene is never remounted, and the camera keeps its relative position.
The Moon’s own orientation is currently an approximate near-static solution: COSMOS does not yet apply a precision libration model, and says so rather than implying a modelled spin.
Sources and further reading
Questions this page answers
- How far is the Moon from Earth today?
- Select today’s UTC date in the calculator and press Calculate. The result is the archived geometric separation at 00:00 UTC, not a continuously live reading or your local midnight. Supported calendar dates are 1 January 2020–31 December 2039.
- How far is the Moon from Earth?
- In the recorded archive the separation ranges from 356,452 km at closest to 406,687 km at the farthest, with a mean of 385,011 km.
- How long does moonlight take to reach Earth?
- About 1.3 seconds. The delay varies slightly with the Moon’s position in its orbit.
- Why is the Moon not always the same distance away?
- Its orbit is elliptical and continuously perturbed, so the Earth–Moon separation changes through every orbit. Both extremes are measured in this archive, and the dates are given rather than averaged away.
Content updated 2026-10-25. The conventional average of 384,400 km / 238,855 miles is sourced to NASA Moon Facts. Calculator results, dated extremes and the sampled mean are computed from the shipped Earth-centred JPL Horizons archive; the conventional average is not claimed as a COSMOS calculation.